| D Willix Plasterers Limited | Construction | 2024 |
| D&B Design and Construction Limited | Construction | 2013 |
| D&C Solving Limited | Construction | 2025 |
| D&Cov Connect Ltd | Transport & logistics | 2023 |
| D&D Marquee Hire Ltd | Administrative & support | 2022 |
| D&D Skilled Brickwork Ltd | Construction | 2021 |
| D&E Glazing Solution Limited | Construction | 2018 |
| D&G Electricians Ltd | Construction | 2018 |
| D&H London Motion Pictures Ltd | Information & communication | 2025 |
| D&K.Goleac Limited | Transport & logistics | 2017 |
| D&L Transport Northampton Ltd | Transport & logistics | 2020 |
| D&M Solutions Limited | Transport & logistics | 2025 |
| D&P Music Limited | Information & communication | 2022 |
| D&S Autos Service Centre Ltd | Wholesale & retail | 2026 |
| D&S Build Services Ltd | Construction | 2024 |
| D&S Enterprise Group Limited | Construction | 2019 |
| D&S Masonry Services Limited | Construction | 2017 |
| D&T Consultant Services Limited | Professional & scientific | 2018 |
| D&V Holdings Ltd | Information & communication | 2021 |
| D&V Maintenance Limited | Construction | 2023 |
| D&Y Tech Services Limited | Administrative & support | 2015 |
| D'Vanest Limited | Education | 2005 |
| D-H-M Investments Ltd | Financial services | 2019 |
| D-H-M Property Investments Ltd | Real estate | 2019 |
| D-H-M Services Ltd | Real estate | 2019 |
| D. M. R. Recycled Autoparts Limited | Water & waste | 1975 |
| D.A Connections Limited | Professional & scientific | 2014 |
| D.A.A. Slinn & Associates Limited | Real estate | 2005 |
| D.A.Bird Limited | Transport & logistics | 1968 |
| D.B. Brickwork Ltd | Construction | 2017 |
| D.C.Horn Electrical Services Ltd | Construction | 2023 |
| D.Coy Fabrications Ltd | Professional & scientific | 2024 |
| D.E.M. Finance Consultants Ltd | Financial services | 2025 |
| D.Fennon Tree Solutions Ltd | Agriculture & fishing | 2023 |
| D.Houghton Limited | Administrative & support | 2005 |
| D.J. Tailby Limited | Construction | 2014 |
| D.M.C Painting & Decorating Ltd | Construction | 2017 |
| D.M.G. Freight Services Limited | Transport & logistics | 1988 |
| D.M.I Luca Trans Ltd | Transport & logistics | 2022 |
| D.O.M. Express Ltd | Transport & logistics | 2014 |
| D.R.C. Holding Company Ltd | Professional & scientific | 2008 |
| D.R.C. Locums Limited | Administrative & support | 2001 |
| D.S. & R.S. Poone Limited | Wholesale & retail | 2008 |
| D.S.Bailey Engineering Ltd | Professional & scientific | 2023 |
| D11 Lounge Ltd | Hospitality | 2023 |
| D2DRIVERS Ltd | Transport & logistics | 2023 |
| D2W Embroidery and Print Limited | Wholesale & retail | 2012 |
| D3SIGN City Limited | Wholesale & retail | 2014 |
| D42 Developments Ltd | Construction | 2018 |
| D777 Ltd | Administrative & support | 2017 |
| D8 Worldwide Solutions Ltd | Wholesale & retail | 2012 |
| DA Clinics Limited | Health & social care | 2007 |
| DA Football Management Limited | Professional & scientific | 2023 |
| DA Store Ltd | Wholesale & retail | 2024 |
| Da-Source Intercontinental Ltd | Professional & scientific | 2018 |
| Dabomb Hair Limited | Other services | 2023 |
| DAC Construction Group Ltd | Construction | 2024 |
| DAC Empowerment CIC | Health & social care | 2025 |
| Dac-Hd Limited | Transport & logistics | 2025 |
| Dach Global Limited | Administrative & support | 2017 |
| Dachser Limited | Transport & logistics | 1975 |
| Daddyfish Farms Limited | Agriculture & fishing | 2025 |
| Daddys Dream Transport Ltd | Transport & logistics | 2021 |
| Dadsnet Limited | Extraterritorial | 2021 |
| Daedalus Consultancy Services Ltd | Professional & scientific | 2017 |
| Daedalus Ltd | Professional & scientific | 2009 |
| Daedalus Ventures Limited | Agriculture & fishing | 2016 |
| Daemon Financial Solutions LLP | | 2009 |
| DAG Grill Limited | Hospitality | 2019 |
| DAG Site Services Ltd | Professional & scientific | 2022 |
| Dagarti CIC | Manufacturing | 2011 |
| Dahab Group Northampton Ltd | Real estate | 2023 |
| Dahiya Ltd | Wholesale & retail | 2025 |
| Dahmer Driving Ltd | Transport & logistics | 2025 |
| Daiakins Ltd | Professional & scientific | 2021 |
| Dainty Rocks Jewellery Ltd | Arts & recreation | 2021 |
| Daisy Atkinson Ltd | Health & social care | 2025 |
| Daisy Chain Day Nursery (Basingstoke) Limited | Health & social care | 2012 |
| Daisy Luxe Group Ltd | Manufacturing | 2026 |
| Daisy-Healthcare Ltd | Health & social care | 2010 |
| DAJ Enterprises Ltd | Administrative & support | 2024 |
| Dajo Solutions Limited | Wholesale & retail | 2003 |
| DAK Medical Ltd | Health & social care | 2025 |
| Dakal Limited | Wholesale & retail | 1995 |
| Dakinb Services Limited | Professional & scientific | 2017 |
| Dakshai Healthcare Limited | Health & social care | 2017 |
| Dakshaip Property Ltd | Real estate | 2023 |
| DAL Engineering Ltd | Professional & scientific | 2024 |
| Dale Escapes Limited | Hospitality | 2025 |
| Dalex Delivery Ltd | Transport & logistics | 2024 |
| Daligas Limited | Energy | 2012 |
| Dallington Court Management Company Limited | Households | 1980 |
| Dalmeny Cromwell Limited | Professional & scientific | 2016 |
| Dals Hart Ltd | Manufacturing | 2019 |
| Dalton Brooke Ltd | Construction | 2026 |
| Dalvi Limited | Construction | 2024 |
| Daly Drainage and Civils Ltd | Professional & scientific | 2025 |
| Dalysconstruction Ltd | Construction | 2025 |
| Damaf Limited | Transport & logistics | 2025 |
| Damar Aircraft Maintenance & Consultancy Limited | Professional & scientific | 2019 |